The invention relates to a friction hinge arrangement for the hinged connection of a cover to a base, for example of a record player, the cover being movable relative to the base between a closed and an open position and being retainable in the open position and in any other position between the closed and the open position with the aid of forces in the friction hinge which counteract the force of gravity on the cover, the arrangement comprising: a hinge member which is movable about a hinge axis between a first position, corresponding to the closed position of a cover, and a second position, corresponding to the open position of a cover, which member has a cylindrical portion which functions as hinge pin and a connection portion which serves for connection to a cover; a plastic friction member which takes the form of a roughly strip-shaped part which is doubled over and which thus comprises two roughly strip-shaped limbs which are interconnected at a bend, the two limbs extending substantially parallel to spaced from each other, and recesses being formed in the limbs at the bend for lodging the hinge pin between the limbs; as well as clamping members for urging the limbs of the friction member towards each other and thus clamping the hinge pin between the limbs.
This type of friction hinge arrangement is used extensively, especially for the hinged connection of transparent plastic covers to record player bases. The arrangement is small and cheap. Securing the arrangement to the base and the cover is simple. For this purpose each of the friction hinge arrangements is secured to the back of the base with the aid of two bolts, which also serve as clamping members for urging the limbs of the friction member towards each other. The hinge members are substantially hook-shaped, one of the limbs of the hook serving as hinge pin and the other limb serving to secure the cover. This connection portion has a cylindrical shape. At its back the plastic cover has two thickened portions, which are each formed with a cylindrical opening in which the cylindrical connections portion of the hinge member is inserted. Thus, a simple step-on operation suffices to attach the cover to the base.
The friction hinge arrangements described in the foregoing owe their popularity to the fact that an important requirement which is imposed in respect of the operation of record players is thus met by simple means. This requirement is that preferably a user can place the cover in any position between its closed and its open position without the cover dropping back into its closed position when it is released. This may not only damage the cover itself, but parts of the record player which are sensitive to shocks may be damaged as well. This is especially so for the bearing of the turntable and the pick-up arm, as well as for the pick-up arm itself and the pick-up element. Moreover, if the cover should drop from an open position when a record is being played, the record is also likely to be damaged.
It is considered a drawback of the known friction hinge arrangement that comparatively great friction forces must be produced in the friction hinges to ensure that the cover remains in its open position even in the most unfavorable situation.